Apple recently updated its popular iMac line of desktop computers to include larger screens, more standard memory and bigger hard drives. Three of the four new configurations—two 21.5-inch models and one 27-inch model—feature 3.06GHz Core 2 Duo processors and are available now. Macworld Lab has the 3.06GHz trio and we’ve put them to the test. (A fourth standard configuration, a 2.66GHz Intel Core i5-based 27-inch model, will be the first iMac to sport a quad-core processor. It should be available later this month.)

The new entry-level iMac has a 21.5-inch LED-backlit screen, a 3.06GHz Intel Core 2 duo processor, 4GB of 1066 DDR3 SDRAM, a 500GB hard drive, and Nvidia GeForce 9400M graphics that shares up 256MB of main memory. This $1199 system replaces an early 2009 model with a 20-inch display, 2.66GHz Core 2 Duo processor, and 2GB of memory. That older model featured the same Nvidia graphics as well as the same price.

The next step up in the new product line is a $1499 model with the same 21.5-inch screen size, memory specifications and processor speeds as the new $1199 iMac, but includes a 1TB hard drive and ATI Radeon HD 4670 graphics with 256MB of dedicated GDDR3 graphics memory. The $1499 model from earlier this year also shipped with 4GB of RAM, but had a larger 24-inch display, a smaller capacity 640GB hard drive, and used the same integrated Nvidia GeForce 9400M graphics as the lower-end model. The third new iMac has the same memory, graphics and storage specs as the new $1499 model, but ships with an expansive 27-inch display and costs $1699. Many of this new 27-inch iMac’s specifications match the high-end iMac released early this year. That $2199 system had a smaller 24-inch display, but came with the same 4GB of RAM and 1TB hard drive as the newer model. The “Early 2009” model also featured discreet graphics, but shipped with NVIDIA GeForce GT 130 graphics with 512MB of dedicated GDDR3 memory.

What do these changes mean in terms of performance? While we can’t yet quote a Speedmark 6 score for these new systems, we did run a lengthy list of tasks on these new iMacs, as well as those they replace in the product line, and found little performance difference between the three new iMacs, with the exception of 3D game performance.

New iMacs (Late 2009)

AdobePhotoshopCS4

Cinebench

Mathematica-Mark 7

Compressor3.0.4

Aperture2.1.4

iMovie ’09

iMovie ’09

iTunes 9

Call of Duty 4

Finder

Finder

Finder

Parallels

Handbrake

iPhoto ’09

Pages ’09

Complete 17Tests

SUITE

RENDER

TEST

MPEG ENCODE

IMPORT

IMPORT ARCHIVE

EXPORT

MP3 ENCODE

FRAME RATE

DUPLICATE 1GB FOLDER

ZIP ARCHIVE

UNZIP ARCHIVE

WORLDBENCH 6 MULTI-TASK TEST

RIP DVD CHAPTER

IMPORT

OPEN WORD DOCUMENT

ALL TIMED TESTS

21.5-inch iMac 3.06GHz (Nvidia)

0:44

2:16

4.23

8:09

2:28

2:14

1:41

1:11

21.9

0:21

2:54

0:46

5:26

2:09

0:32

1:32

31 minutes, 47 seconds

21.5-inch iMac 3.06GHz (ATI)

0:41

2:15

4.42

8:06

2:32

2:16

1:18

1:16

69.1

0:23

2:55

0:43

5:20

2:20

0:32

1:33

31 minutes, 41 seconds

27-inch iMac 3.06GHz

0:42

2:15

4.28

8:16

2:36

2:17

1:16

1:16

66.6

0:22

3:00

0:39

5:21

2:23

0:32

1:31

32 minutes, 11 seconds

24-inch iMac 3.06GHz (Early 2009)

0:41

2:13

4.73

7:57

2:33

2:16

1:29

1:16

67.2

0:22

2:46

0:44

4:54

2:12

0:31

1:31

30 minutes, 53 seconds

24-inch iMac 2.93GHz (Early 2009)

0:47

2:20

4.51

8:23

2:41

2:21

1:35

1:16

45.1

0:23

3:05

0:41

5:14

2:16

0:36

1:45

32 minutes, 45 seconds

20-inch iMac 2.66GHz (Early 2009)

0:47

2:33

4.22

9:03

3:10

1:40

1:53

1:28

19.2

0:25

3:42

0:51

5:46

2:24

0:36

2:01

35 minutes, 35 seconds

Best results in bold. For Call of Duty 4 and MathematicaMark 7, higher scores are better. All other tests are timed results where lower times are better. Reference systems in italics.

Call of Duty score is in frames per second. MathematicaMark is a performance score. All others are in minutes:seconds. All systems were tested with 10.6.1 with 4GB of RAM. The Photoshop Suite test is a set of 14 scripted tasks using a 50MB file. Photoshop’s memory was set to 70 percent and History was set to Minimum. We recorded how long it took to render a scene with multiprocessors in Cinebench. We used Compressor to encode a .mov file to the application's H.264 for video podcast setting. We timed the import and thumbnail/preview creation time for 150 photos. In iMovie '09, we imported a camera archive and exported it to iTunes using the Mobile Devices setting. We converted 90 minutes of AAC audio files to MP3 using iTunes’ High Quality setting. We duplicated a 1GB folder, created a Zip archive in the Finder from the two 1GB files and then Unzipped it. We ran WorldBench 6 multitasking test on a Parallels VM. We imported 150 JPEGs into iPhoto '09. We ripped a DVD chapter to the hard drive and opened a 500 page Word document in Pages '09.—Macworld Lab testing by James Galbraith, Chris Holt, Helen Williamson, and Roman Loyola.

Looking at the total time it took to run 17 different timed tests, we see only 30 seconds separating the fastest iMac in our tests, the 21.5-inch 3.06GHz system with 1TB hard drive and ATI graphics (which finished the tests in 31 minutes, 41 seconds) and the slowest of the new iMacs, the 27-inch 3.06GHz system (which took 32 minutes, 11 seconds). The new $1199 iMac with the 500TB hard drive and Nvidia graphics finished the suite of tests just 6 seconds behind the leader.

The cumulative results doesn’t include results for our Call of Duty test, which the two ATI Radeon HD 4670-equipped iMacs won handily, posting frame rates at least three times as fast as the new Nvidia-equipped $1199 iMac. iPhoto times for the three new iMacs were identical, while Cinebench, iMovie import, Pages, and our file duplication tests were all just a second or two off from each other. The one baffling test result was the iMovie export, which was considerably slower on the new low-end iMac. We retested each system several times, but the times were consistent.

Comparing the new iMacs to the $2199 3.06GHz 24-inch model from early this year, we also found very little difference in performance—that in itself says a lot. The new 27-inch, 3.06GHz model costs $500 less than the older model, and if you can go with a 21.5 inch screen instead of a 24-inch one, you can save $700 and still have very similar performance. If you’re not an avid gamer, the new entry-level iMac costs $1000 less and was neck and neck with the older system in all but our Call of Duty test. Down the road, when more applications take advantage of GPU processing power through OpenCL, the performance differences might become more apparent, but for now, the $1199 iMac looks like a super deal.

Comparing the new entry-level iMac to the system it replaces, the 2.66GHz 20-inch iMac, we found the new system took 11 percent less time to complete our suite of tests. We tested both systems with 4GB of RAM, which levels the performance playing field, but also affects the price of the earlier model.

Check back soon for our complete review of the new iMacs as well an introduction of our new system performance test suite Speedmark 6.

[James Galbraith is Macworld’s lab director.]

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